Ye cows don't much like koalas.
They used to get on OK but there's been a lot of deforestation and Koalas have found it hard making a living. Many of them have taken jobs on alien research ships as anal probe technicians, they have an aptitude for it apparently. Anyway we all know the bovine ass is of particular interest to alien folk and well, cows know how to hold a grudge and koalas just have to bear it, even though they're not bears.
They used to get on OK but there's been a lot of deforestation and Koalas have found it hard making a living. Many of them have taken jobs on alien research ships as anal probe technicians, they have an aptitude for it apparently. Anyway we all know the bovine ass is of particular interest to alien folk and well, cows know how to hold a grudge and koalas just have to bear it, even though they're not bears.